The reproductive pattern of an insectivorous bat (Hipposideros larvatus) and a frugivorous bat (Cynopterus horsfieldi) from an agriculture area, Kuala Perlis (6° 26' N, 100° 8' E), Peninsular Malaysia, is described. Insectivorous bats were sampled monthly from January 2000 to January 2001, while frugivorous bats were collected from April 2000 to March 2001. Microscopic observation of the seminiferous tubules and ductus epididymides in both species of male bats showed that they were synchronized in the presence or absence of spermatozoa. In H. larvatus, the presence of spermatozoa was only detected from May to September and the same goes for Graafian and corpus luteum follicles. For C. horsfieldi, the spermatogenesis process occurred throughout the study period but there were certain months where the presence of spermatozoa was not detected in seminiferous tubules. The former was found to show a restricted seasonal monoestry and had a synchronous reproductive pattern, with copulation immediately followed by fertilization and pregnancy. The gestation period was three months and the left uterine horn was dominant. While in the latter, female bats possessed a bilaterally functional reproductive system, whereby implantation can occur on either side of the uterine horn. The reproductive pattern of this species was seasonally polyoestrous with a gestation period of three months. This species had two reproductive seasons (October-December and March-May) in a year with each female produced one litter from each pregnancy.